Technical Field
The present invention generally relates to semiconductor devices, and more particularly to substrates and methods for fabrication that yield a compressive strain employed for formation of semiconductor devices.
Description of the Related Art
Strained silicon and strained silicon-on-insulator (SOI) can provide enhanced properties for semiconductor devices. For example, p-type field effect transistors (PFETs) have improved performance when formed with a compressive strain channel, and n-type field effect transistors (NFETs) have improved performance when formed with a tensile strain channel. Tensile strain devices are easily formed using, e.g., relaxed SiGe buffer layers or SiGe condensation. Compressively strained silicon is much more difficult to achieve. Globally compressive strained substrates are not presently known.